aboutsummaryrefslogtreecommitdiffstats
path: root/lib/kernel/doc/src
diff options
context:
space:
mode:
Diffstat (limited to 'lib/kernel/doc/src')
-rw-r--r--lib/kernel/doc/src/app.xml2
-rw-r--r--lib/kernel/doc/src/code.xml136
-rw-r--r--lib/kernel/doc/src/heart.xml63
3 files changed, 200 insertions, 1 deletions
diff --git a/lib/kernel/doc/src/app.xml b/lib/kernel/doc/src/app.xml
index d6d6167923..35feec144e 100644
--- a/lib/kernel/doc/src/app.xml
+++ b/lib/kernel/doc/src/app.xml
@@ -201,7 +201,7 @@ RTDeps [ApplicationVersion] []
how to compare application versions see
<seealso marker="doc/system_principles:versions">the
documentation of versions in the system principles
- guide</seealso>. Note that that the application version
+ guide</seealso>. Note that the application version
specifies a source code version. An additional indirect
requirement is that installed binary application of
the specified version has been built so that it is
diff --git a/lib/kernel/doc/src/code.xml b/lib/kernel/doc/src/code.xml
index d4c9a48901..819da544c3 100644
--- a/lib/kernel/doc/src/code.xml
+++ b/lib/kernel/doc/src/code.xml
@@ -310,6 +310,10 @@
<datatype>
<name name="load_error_rsn"/>
</datatype>
+ <datatype>
+ <name name="prepared_code"/>
+ <desc>An opaque term holding prepared code.</desc>
+ </datatype>
</datatypes>
<funcs>
@@ -479,6 +483,138 @@
</desc>
</func>
<func>
+ <name name="atomic_load" arity="1"/>
+ <fsummary>Load a list of modules atomically</fsummary>
+ <desc>
+ <p>Tries to load all of the modules in the list
+ <c><anno>Modules</anno></c> atomically. That means that
+ either all modules are loaded at the same time, or
+ none of the modules are loaded if there is a problem with any
+ of the modules.</p>
+ <p>Loading can fail for one the following reasons:</p>
+ <taglist>
+ <tag><c>badfile</c></tag>
+ <item>
+ <p>The object code has an incorrect format or the module
+ name in the object code is not the expected module name.</p>
+ </item>
+ <tag><c>nofile</c></tag>
+ <item>
+ <p>No file with object code exists.</p>
+ </item>
+ <tag><c>on_load_not_allowed</c></tag>
+ <item>
+ <p>A module contains an
+ <seealso marker="doc/reference_manual:code_loading#on_load">-on_load function</seealso>.</p>
+ </item>
+ <tag><c>duplicated</c></tag>
+ <item>
+ <p>A module is included more than once in
+ <c><anno>Modules</anno></c>.</p>
+ </item>
+ <tag><c>not_purged</c></tag>
+ <item>
+ <p>The object code can not be loaded because an old version
+ of the code already exists.</p>
+ </item>
+ <tag><c>sticky_directory</c></tag>
+ <item>
+ <p>The object code resides in a sticky directory.</p>
+ </item>
+ <tag><c>pending_on_load</c></tag>
+ <item>
+ <p>A previously loaded module contains an
+ <c>-on_load</c> function that never finished.</p>
+ </item>
+ </taglist>
+ <p>If it is important to minimize the time that an application
+ is inactive while changing code, use
+ <seealso marker="#prepare_loading/1">prepare_loading/1</seealso>
+ and
+ <seealso marker="#finish_loading/1">finish_loading/1</seealso>
+ instead of <c>atomic_load/1</c>. Here is an example:</p>
+<pre>
+{ok,Prepared} = code:prepare_loading(Modules),
+%% Put the application into an inactive state or do any
+%% other preparation needed before changing the code.
+ok = code:finish_loading(Prepared),
+%% Resume the application.</pre>
+ </desc>
+ </func>
+ <func>
+ <name name="prepare_loading" arity="1"/>
+ <fsummary>Prepare a list of modules atomically</fsummary>
+ <desc>
+ <p>Prepares to load the modules in the list
+ <c><anno>Modules</anno></c>.
+ Finish the loading by calling
+ <seealso marker="#finish_loading/1">finish_loading(Prepared)</seealso>.</p>
+ <p>This function can fail with one of the following error reasons:</p>
+ <taglist>
+ <tag><c>badfile</c></tag>
+ <item>
+ <p>The object code has an incorrect format or the module
+ name in the object code is not the expected module name.</p>
+ </item>
+ <tag><c>nofile</c></tag>
+ <item>
+ <p>No file with object code exists.</p>
+ </item>
+ <tag><c>on_load_not_allowed</c></tag>
+ <item>
+ <p>A module contains an
+ <seealso marker="doc/reference_manual:code_loading#on_load">-on_load function</seealso>.</p>
+ </item>
+ <tag><c>duplicated</c></tag>
+ <item>
+ <p>A module is included more than once in
+ <c><anno>Modules</anno></c>.</p>
+ </item>
+ </taglist>
+ </desc>
+ </func>
+ <func>
+ <name name="finish_loading" arity="1"/>
+ <fsummary>Finish loading a list of prepared modules atomically</fsummary>
+ <desc>
+ <p>Tries to load code for all modules that have been previously
+ prepared by
+ <seealso marker="#prepare_loading/1">prepare_loading/1</seealso>.
+ The loading occurs atomically, meaning that
+ either all modules are loaded at the same time, or
+ none of the modules are loaded.</p>
+ <p>This function can fail with one of the following error reasons:</p>
+ <taglist>
+ <tag><c>not_purged</c></tag>
+ <item>
+ <p>The object code can not be loaded because an old version
+ of the code already exists.</p>
+ </item>
+ <tag><c>sticky_directory</c></tag>
+ <item>
+ <p>The object code resides in a sticky directory.</p>
+ </item>
+ <tag><c>pending_on_load</c></tag>
+ <item>
+ <p>A previously loaded module contains an
+ <c>-on_load</c> function that never finished.</p>
+ </item>
+ </taglist>
+ </desc>
+ </func>
+ <func>
+ <name name="ensure_modules_loaded" arity="1"/>
+ <fsummary>Ensure that a list of modules is loaded</fsummary>
+ <desc>
+ <p>Tries to load any modules not already loaded in the list
+ <c><anno>Modules</anno></c> in the same way as
+ <seealso marker="#load_file/1">load_file/1</seealso>.</p>
+ <p>Returns <c>ok</c> if successful, or
+ <c>{error,[{Module,Reason}]}</c> if loading of some modules fails.
+ See <seealso marker="#error_reasons">Error Reasons for Code-Loading Functions</seealso> for a description of other possible error reasons.</p>
+ </desc>
+ </func>
+ <func>
<name name="delete" arity="1"/>
<fsummary>Removes current code for a module</fsummary>
<desc>
diff --git a/lib/kernel/doc/src/heart.xml b/lib/kernel/doc/src/heart.xml
index b9fad17ce1..9da4773f2d 100644
--- a/lib/kernel/doc/src/heart.xml
+++ b/lib/kernel/doc/src/heart.xml
@@ -118,6 +118,13 @@
<p>In the following descriptions, all function fails with reason
<c>badarg</c> if <c>heart</c> is not started.</p>
</description>
+
+ <datatypes>
+ <datatype>
+ <name name="heart_option"/>
+ </datatype>
+ </datatypes>
+
<funcs>
<func>
<name name="set_cmd" arity="1"/>
@@ -154,6 +161,62 @@
the empty string will be returned.</p>
</desc>
</func>
+
+ <func>
+ <name name="set_callback" arity="2"/>
+ <fsummary>Set a validation callback</fsummary>
+ <desc>
+ <p> This validation callback will be executed before any heartbeat sent
+ to the port program. For the validation to succeed it needs to return
+ with the value <c>ok</c>.
+ </p>
+ <p> An exception within the callback will be treated as a validation failure. </p>
+ <p> The callback will be removed if the system reboots. </p>
+ </desc>
+ </func>
+ <func>
+ <name name="clear_callback" arity="0"/>
+ <fsummary>Clear the validation callback</fsummary>
+ <desc>
+ <p>Removes the validation callback call before heartbeats.</p>
+ </desc>
+ </func>
+ <func>
+ <name name="get_callback" arity="0"/>
+ <fsummary>Get the validation callback</fsummary>
+ <desc>
+ <p>Get the validation callback. If the callback is cleared, <c>none</c> will be returned.</p>
+ </desc>
+ </func>
+
+ <func>
+ <name name="set_options" arity="1"/>
+ <fsummary>Set a list of options</fsummary>
+ <desc>
+ <p> Valid options <c>set_options</c> are: </p>
+ <taglist>
+ <tag><c>check_schedulers</c></tag>
+ <item>
+ <p>If enabled, a signal will be sent to each scheduler to check its
+ responsiveness. The system check occurs before any heartbeat sent
+ to the port program. If any scheduler is not responsive enough the
+ heart program will not receive its heartbeat and thus eventually terminate the node.
+ </p>
+ </item>
+ </taglist>
+ <p> Returns with the value <c>ok</c> if the options are valid.</p>
+ </desc>
+ </func>
+ <func>
+ <name name="get_options" arity="0"/>
+ <fsummary>Get the temporary reboot command</fsummary>
+ <desc>
+ <p>Returns <c>{ok, Options}</c> where <c>Options</c> is a list of current options enabled for heart.
+ If the callback is cleared, <c>none</c> will be returned.</p>
+ </desc>
+ </func>
+
+
</funcs>
</erlref>